The invention relates to a high availability control method for railway door systems, making it possible, in case of failure, to have the possibility to open and close the doors of a railway car, and also relates to an on-panel system for implementing such a method. The invention applies to the door accessories, in particular to sound output devices for loudspeakers and to latch fittings, as well as to door environments in connection with the railway communication network lines.
Here, railway car or car means a rigid unit for railway transportation, an assembly of railway cars connected together and constituting a train set, a tramway or any rail-guided transportation means. A “door system” includes all the control means in particular the control panel, the mechanical means of the door proper, as well as the electromechanical accessories such as sensors, activators; push-buttons, buzzers, loud-speakers, warning lights, limit switch elements etc.
Statistically, failures of passenger railway transportation can be attributed to access doors in a proportion of approximately 30 to 40%. Besides, the door control electronics amounts to 40 to 50% of all the failures of such doors. In order to improve such availability, it is known to increase the frequency of the equipment maintenance. Thus, document EP 0 728 894 discloses an emergency control allowing to open the doors in case of a failure of the main power supply. Such type of solution is expensive and requires an increased immobilization of cars.
It is also well known to add, to the existing system, a system which is a dual door control means to preserve the control in case of a failure of a system. However, this solution is also expensive and multiplies the number of components to be used. Such multiplication entails a substantially lower reliability, since the risk of failure then increases in the same proportions as the number of components.
Thus, the invention aims at increasing the availability of the door systems without affecting the reliability of the control system. For this purpose, the invention provides to take advantage of the alternative operation of the door systems positioned, on either side of a car. More precisely, the object of the invention is to provide a high availability control method for railway door systems of a car, positioned along two opposite longitudinal sides of the car, consisting in detecting a failure control of a first accessory whose opening or closing has been requested, transmitting the failing control to the operational control of at least one associated accessory, positioned along the opposite longitudinal side, and substituting the failing control with said associated operational control. Such a method makes it possible not to duplicate the equipment of a train while keeping a high availability of operation of the doors whose opening or closing has been requested.
According to particular embodiments of the method:                the associated accessories are automatically managed by a mutual checking of the controls through periodical exchanges between both controls and a takeover of an assumed failing control in the absence of a periodical detection, by neutralizing such control and by transferring the opening authorizations to the associated control from a combination between a low speed signal and a validation side selection signal;        the environmental and functionality information of each door are analyzed in order to detect operation anomalies, and if need be, to perform a new substitution;        when the door is provided with a position encoder, the position information may not be sent back to the control of the associated door, for saving time, and the failing door is thus operated, in case of failure, on the basis of position calculation algorithms.        
The invention also relates to a high availability on-panel control system for the doors of a car, for the implementation of such method. Such system includes mutual checking means for associated control panels in order to transmit authorization signals of the exclusive opening of one of the two series of the opposite side doors, and the checking means combine a low speed signal and a validation side selection signal to perform, in each environment, opening/closing authorizations to the motor control of its system and to the motor control of the associated system.
Each door control panel preferably receives door position signals and sends signals for triggering the environmental conditioning devices for example lamps and buzzers, as well as the control means of the driving motor of the corresponding door. The word “panel” means an electronic control unit, dedicated here to the control of a car door and of the accessories of its environment connected to its close perimeter.
According to particular embodiments:                each door control panel receives door position signals and sends signals for triggering the environmental conditioning devices, as well as the control means of the driving motor of the corresponding door;        each door panel comprises switching means between the control means of the motor of a door and control means of the motor of at least one associated door, positioned on an opposite side wall, said position and triggering signals being then capable of being sent to the panel of the associated door in order to transfer the door control to the latter;        the position and triggering signals of a door are digital and transmitted to the associated remote door panel via a signal inlet/outlet module;        a transmission bus performs the transmission of the data from the inlet/outlet module of the panel of a door to the panel of the associated door;        life lines perform a mutual checking by connecting the panel of each door to the panel of each associated door in order to transmit the periodically refreshed control signals;        the triggering of the emergency procedure is generated from a life line continuum;        a filtering time is predetermined between a stoppage of the variation of the line control signal and the triggering of the intervention means on a failing panel by comparing the value of each signal;        the control means on a failing panel comprise means for stopping its power supply, power switches of the corresponding motor to the motor control circuit of the associated operational panel, in connection with the authorization control means for the opening of the doors on the opposite sides and means for locking the direction of motors;        the motor power switches between two associated panels activate, for each panel, an H bridge motor driving circuit having between terminals for selecting the motors to be driven, the takeover terminals being connected to the emergency mode terminals by means of connections, each circuit including the means for locking the direction of motors;        the opening authorizations controlling means are locked by a processing of the door speed and the opening or closing authorization signals for the doors on each side, according to a double, i.e. positive and negative, validation logic suite, in order to make the selection of the takeover of the motorization of a door on one side depend on the validation of an opening authorization on this side.        
In order to guarantee the continuous operation of the door environment communication networks, the operational panel emulates a “network behavior” of the associated failing panel, either by neutralizing the failing panel or by driving a “bypass” (branching) of the network line at the level of the failing panel, thus keeping the failing panel on. The invention also applies to the accessories of the railway doors, more particularly the information diffusion loudspeakers and the door latch fittings. In the case where accessories are railway door environments loudspeakers, the failing control of a door environment loudspeaker being transferred to the operational control of the loudspeaker of the associated door environment. Advantageously, the control of the failing panel of a door environment loudspeaker is transferred to the control of the associated panel of a emergency loudspeaker of that environment.
According to another embodiment, each door control panel and the panel of the associated door have access to the same module sound generation module via transmission buses, each module supplying sound signals to at least one loudspeaker of each door environment, each module being positioned in each door environment. In the case of railway doors electric latch fittings, a switching of the control of each latch fitting, during the transfer of the control in emergency mode, is carried out according to the preceding method and the locking of the controls is carried by a logic gate of opening authorizations of a door system and a control through the logic gate of the opening authorization of the associated environment.